The present invention relates to a centrifuge adapted for use with a plurality of types of rotors of different maximum revolving speeds and, more particularly, to an arrangement for automatically discriminating the type of rotor mounted on the rotary shaft of a motor of the centrifuge.
In this kind of centrifuge, a permissible maximum revolving speed is determined according to the type of rotor used and driving at a speed higher than the maximum revolving speed entails a danger of an accident, such as breakage of the rotor or the centrifuge. It is general practice in the prior art that predetermined permissible maximum revolving speeds of rotors are changed over by an operator through a switch or the like in accordance with the rotor to be used, and that when the revolving speed of the rotor exceeds its permissible maximum speed, the motor drive power source is automatically cut off, thus preventing an accident. With such a conventional centrifuge, however, since the permissible maximum revolving speed is set by the operator in accordance with the rotor to be used, it is likely that the operator makes a mistake in setting the revolving speed or forgets to set it. For example, an angle rotor is driven at a maximum revolving speed of 15,000 rpm and a swing rotor 12,000 rpm. It has often been the case that the swing rotor is driven at the maximum revolving speed of the angle rotor, resulting in breakage of the swing rotor or the centrifuge.